1. Field of the Invention
The present invention relates to a push switch usable for various kinds of electronic devices.
2. Description of the Related Art
The construction of a conventional, prior art push switch will be described with reference to FIG. 4. Such a push switch includes: a case 16; a contact piece 9; a sliding body 10; and a cover 11.
The case 16 is formed substantially in a rectangular, parallelepiped shape and includes a fixed terminal 7 having a fixed contact 7a and a fixed terminal 8 having a fixed contact 8a on the inner bottom surface thereof.
The contact piece 9 is made of a conductive material having elasticity and includes: a fulcrum portion 9b; a bent portion 9a; and tongue pieces 9e and 9f. The fulcrum portion 9b is formed by outwardly bending an end portion of one side thereof so as to turn up. The bent portion 9a is bent substantially in a U shape. The tongue pieces 9e, 9f, are provided in the top end of the opposite side and have movable contacts 9c and 9d, respectively.
The sliding body 10 includes a bar portion and a suppressing portion 10a. The suppressing portion 10a is provided under the bar portion in order to suppress the upper part of the bent portion 9a of the contact piece 9. The sliding body 10 slides in the longitudinal direction.
The cover 11 engages the case 16, and includes an aperture 11a for enabling the sliding body 10 to slide therethrough and retaining the sliding body 10 and a concave portion 11c. The cover 11 and the case 16 support the contact piece 9 so that the fulcrum portion 9b of the contact piece 9 can rotate. More specifically, the contact piece 9 is interposed between the concave portion 11c provided in the lower bottom of the cover 11 and the inner bottom surface of the case 16.
Hereinafter, the operation of a conventional push switch having such a construction will be described with reference to FIGS. 5 and 6.
FIG. 5 is a side sectional view showing a conventional push switch in an OFF state. The movable contact 9c is always in contact with the fixed contact 7a. The upper part of the bent portion 9a is in contact with the suppressing portion 10a provided under the bar portion of the sliding body 10.
When a user depresses the sliding body 10, the conventional push witch is placed in an ON state as shown in FIG. 6. At this time, the bent portion 9a rotates around the fulcrum portion 9b at the center axis while bending the contact piece 9. The movable contact 9c is always in contact with the fixed contact 7a. As shown in FIG. 6, when the push switch is in the ON state, the movable contact 9d is in contact with the fixed contact 8a.
When the user removes the force depressing the sliding body 10, the recovery force of the contact piece 9 returns the conventional push switch to the OFF state as shown in FIG. 5. In this case, the contact piece 9 generates an angular moment in the clockwise direction.
However, when the push switch is in the OFF state, the height of the push switch increases by the thickness of the suppressing portion 10a of the sliding body 10 which is in contact with the upper part of the bent portion 9a. Therefore, it has been difficult to downsize such a conventional push switch.